Society Islands beach bum black flies (Diptera: Simuliidae)

2017·9.1 MB·English

by  Douglas A. Craig

Zootaxa 4311 (3): 373–388 ISSN 1175-5326 (print edition)
Article ZOOTAXA
http://www.mapress.com/j/zt/
Copyright © 2017 Magnolia Press ISSN 1175-5334 (online edition)
https://doi.org/10.11646/zootaxa.4311.3.3
http://zoobank.org/urn:lsid:zoobank.org:pub:9A5CF14E-E098-45E3-B6DB-C52773FD7F14
Society Islands beach bum black flies (Diptera: Simuliidae)
DOUGLAS A. CRAIG1 & NEAL L. EVENHUIS2
1Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada, T6G 2E9.
E-mail: [email protected]. orcID: 0000-0002-9269-8826
2Pacific Biological Survey, Bishop Museum, 1525 Bernice Street, Honolulu, Hawai‘i 96817-2704, USA.
E-mail: [email protected]. orcID: 0000-0002-1314-755X
Abstract
Aspects of the body of work on the Central and Western Pacific black fly Simulium (Inseliellum) are briefly reviewed.
Female adults collected from beaches in Tahiti and Raiatea are described as Simulium (Inseliellum) littopyga n. sp., Sim-
ulium (Inseliellum) littosocius n. sp. and Simulium (Inseliellum) littosodalis n. sp.. Immature stages of the three species
are not associated.
Key words: Simuliidae, Simulium, Inseliellum, Society Islands, new species
Preliminary discourse
The wide-ranging Pacific simuliid subgenus of Inseliellum has been well examined. The segregate is known from
Micronesia and the Cook, Austral, Society and Marquesas Islands. In the Marquesas Islands Simulium buissoni
Roubaud is known to bite humans and poultry, with S. gallinum Edwards only ornithophilic (Edwards 1927, 1932,
Lavondes & Pichon 1972). Indeed, biting by females of S. buissoni was serious enough that they were referred to
as the “Scourge of the Pacific” (Edwards 1932, Cheesman 1932) and the species subject to unsuccessful
eradication attempts (Fossati & Séchan 1993, Craig et al. 1995, Englund 2008). Of some relevance to this present
work, females of S. buissoni are known to fly considerable distances for a blood meal—even out to moored boats to
feed on the inhabitants (Cheesman 1932: 94, Craig 1995: 775).
Of note for Tahiti, larvae of Simulium oviceps Edwards, with small labral fans plus concomitant narrowed
anterior head, have received considerable attention (Grenier & Rageau 1960, Dumbleton 1962, Davies 1965, Craig
1974, 1975, 1977, 1987), in major part because the head shows similarities to those of fan-less Gymnopais and
Twinnia larvae of Prosimuliini—a similarity that is now known to be an independent development (Currie & Craig
1987). Adults of S. oviceps are amongst the smallest known simuliids and have not been recorded as blood feeding.
While common, that species is less so than S. tahitiense Edwards.
The range of labral fan expression in Polynesian simuliid larvae was integral to a model of fan structure in
relation to habitat parameters (Palmer & Craig 2000). Filter-feeding behaviour of Tahitian larvae has been
investigated in detail by Schröder (1985, 1988).
Simulium tahitiense immatures are common in the larger rivers of Tahiti and can occur in astronomical
numbers. The adults, of moderate size, are often a considerable nuisance, but are not recorded, specifically, as
biting. Indeed, the females do not fly more than some metres from running water (Cheesman 1932: 96, DAC pers.
obs.). On the other hand, female Simulium cheesmanae Edwards—of distinct yellow colour and amongst the
largest of known simuliids, do fly well away from running water and are definitively known to bite humans (Craig
1987, 1997).
Up until the study by Craig (1987), only three species of simuliids were known from Tahiti: S. tahitiense, S.
oviceps and S. cheesmanae; the last only from adults. The discovery that Tahitian simuliids inhabited cascades
(e.g., S. cataractarum Craig 1987) changed the search paradigm of habitats and led to numerous species from
Accepted by L. Hernandez-Triana: 30 May 2017; published: 24 Aug. 2017 373
unusual habitats, mainly madicolous flows (thin films of water). With the three new species described here,
numbers now presently total some 34 for Tahiti and 56 for Polynesia as a whole (Craig & Joy 2000, Craig 2004,
Adler & Crosskey 2017). An estimate as to possible numbers of simuliid species for Tahiti was made by Craig
(1987: 408) and later (Craig 1997: 869, Craig 2004: 2). All were incorrect because numbers of the species
described were eventually shown to be species complexes. Not only will unusual habitats need further
examination, time of year of collection is here suggested as important for discovering new species.
Nonetheless, this now-recognized species radiation, plus known ages of Polynesian hot-spot islands led to
phylogenetic (e.g., Craig & Currie 1999, Craig et al. 2001), cytological (Spironello et al. 2002), molecular- and
genetic-based examinations (Joy & Conn 2001, Joy et al. 2007), plus biogeographic speculation (e.g. Craig 2003),
and was used to test the McArthur-Wilson biogeographic model (e.g. Spironello & Brooks 2003).
Despite the amount of collecting effort since the late 1920s, no simuliid from the Society Islands has ever been
reported as collected from a beach, this despite considerable time spent in such places by various collectors.
However, as part of general collecting of aquatic Diptera of Tahiti and Raiatea (a component of a grant-funded
terrestrial arthropod survey of French Polynesia), adults of previously unknown simuliids were collected along
beaches (e.g., Fig 42).
An overarching problem for Society Island simuliids is that the majority of species are known only from
distinctive larvae; neither pupae nor adults having ever been associated. As noted below, the possibility exists that
the three species described here from female adults have already been described as immatures.
Material and methods
Examination follows that of Craig et al. (2012). Original alcohol material was dried using Peldri II™. All images
are by DAC except where noted. Individual labels are indicated by square brackets [ ] with a slash (/) to indicate a
new line of text. All material is deposited in the Bernice P. Bishop Museum, Honolulu (BPBM).
Simulium (Inseliellum) littopyga Craig & Evenhuis, n. sp.
Figs. 1–15.
Description. Adult female (based on 21 specimens). Body (Figs. 1): overall dark brown, abdomen occasionally
mottled ventrally; total length 2.0–2.6 mm. Head (Fig. 2): width 0.79 mm; depth 0.57 mm; postocciput with sparse
black hairs; frons black, decreased slightly in width ventrally, with sparse hairs laterally, frons/head ratio 1.0:17.0;
frontal angle 50º. Eye: dark orange, interocular distance 0.1 mm; ommatidia diameter 0.014 mm; ca. 24 rows
across and 30 down at mid-eye. Clypeus: width 0.2 mm; blackish brown, bare. Antenna (Figs. 2, 3): not markedly
extended beyond head margins, overall clear pale yellow, nine flagellomeres; total length 0.55 mm; scape and
pedicel slightly darker, pedicel rounded; flagellomere I square; flagellomere II twice as wide as long, III–VIII
similar in shape, gradually increased in length, flagellomere IX cone shaped. Mouthparts: not markedly developed,
ca. 0.3x length of head depth; maxillary palp (Fig. 4) length 0.56 mm, palpomeres I and II small, palpomere III
small and sub-cylindrical, sensory vesicle occupying half of palpomere, palpomere V subequal in length to
remainder of palp, proportional lengths of palpomeres III–V 1.0:1.3:2.6, respectively; mandible (Figs, 4, 5) slightly
flared apically with ca. 19 small blunt inner teeth, outer teeth absent; lacinia with 15 and 13 teeth on inner and outer
edge respectively; cibarium (Fig. 6) with cornuae sclerotized apically, lightly sculpted, median gap angulate.
Thorax: length 1.0–1.1 mm; width 0.8–0.9 mm; evenly blackish brown, with sparse fine pale vestiture;
postpronotal lobe well developed with vestiture as for scutum; antepronotal lobe with sparse hairs; proepisternum
with clump of hairs, fore coxa with sparse hairs; scutellum concolourous with scutum, vestiture of longer hairs, V-
shaped apically, markedly overhanging the postnotum; postnotum concolourous with scutum, pollinose anteriorly,
bare; anepisternal membrane bare (Fig. 8); katepisternum dark brown, sulcus distinct. Wing (Fig. 7): membrane
slightly dusky on apex and anal lobe, length 2.1–2.4 mm; width 1.1–1.2 mm; anterior veins markedly expressed;
costa with mixture of thin hairs and short substantial spines; subcosta bare apically; radius with spines and hairs; a/
b ratio 1.0:3.6; r-m cross vein slightly pigmented; basal medial cell well expressed; M slightly doubled; CuA not
1 2
markedly sinuous; A extended nearly to wing margin; narrow sclerotised crescent in anal lobe angle. Haltere:
2
white. Legs: overall yellow; fore and mid legs with tarsomeres brown; hind legs yellow with distal end of
374 · Zootaxa 4311 (3) © 2017 Magnolia Press CRAIG & EVENHUIS
FIGURES 1–6. Simulium (I) littopyga n. sp. (1). Holotype, female Simulium (I.) littopyga. In ETOH. Scale bar = 0.5 mm. (2)
Frontal view of head. Scale bar = 0.2 mm. (3). Antenna. Scale bar = 0.1 mm. (4). Maxillary palp, mandible, lacinia. Scale bar =
0.1 mm. (5). Mandible apex. Scale bar = 0.02 mm. (6). Cibarium. Scale bar = 0.05 mm.
SOCIETY ISLANDS BEACH SIMULIIDAE Zootaxa 4311 (3) © 2017 Magnolia Press · 375
FIGURES 7–11. Simulium (I.) littopyga n. sp. (7). Wing. Scale bar = 0.5 mm. (8). Anepisternal membrane. Scale bar = 0.1
mm. (9). Hind basitarsus, calcipala, pedisulcus. Scale bar = 0.1 mm. (10). Claw & basal tooth. Scale bar = 0.05 mm. (11).
Abdominal tergites. (Holotype, dried). Scale bar = 0.5 mm.
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FIGURES 12–15. Simulium (I.) littopyga n. sp. (12). Hypogynial valves. Scale bar = 0.1 mm. (13). Spermatheca. Scale bar =
0.02 mm. (14). Genital fork. Scale bar = 0.05 mm. (15). Cercus & anal lobe. Scale bar = 0.05 mm.
basitarsus brown as are other tarsomeres; hind basitarsus narrowed, ventral regular row of stout spines proximally,
less so distally; calcipala slightly flared laterally, half width of tarsomere, as long as wide; pedisulcus distinct;
tarsomere II about 2.0–2.2 times as long as distal width (Fig. 9); claw (Fig. 10) with main talon well curved and
evenly tapered, basal tooth 0.25x length of claw, thumb-like, heel small. Abdomen (Fig. 11): basal scale vestiture
short, barely reaching tergite II; tergites II–VI well sclerotized, vestiture essentially absent from tergites II–IV,
tergite II 5x wider than long, tergite III 3x wider than long, tergite IV 2x wider than long, ovoid, tergites V and VI
3x wider than long, tergites VII and VIII not markedly expressed, with vestiture of sparse pale scales. Genitalia:
markedly small, yellowish; sternite VIII with distinct depression medially, with large strong hairs posterolaterally;
hypogynial valves (Fig. 12), lightly pigmented, vestiture of triads of microtrichia and strong hairs, valves markedly
separated, median edges of valves broadly concave and strengthened, rounded apically; spermatheca spherical,
small, but strongly expressed (Fig. 13), surface lightly wrinkled, internal spines (acanthae) absent, membranous
area at junction with spermathecal duct not distinct; genital fork (Fig. 14) with stem narrowed, not expanded
apically, lateral arms moderately spread with lightly strengthened medial edges, lateral plates not markedly
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expressed, apodeme distinct; cercus in lateral view small, broadly rounded, with marked cluster of stiff setae
apically, anal lobe small, rounded (Fig. 15).
Male: unknown.
Immatures: not associated.
Material. Holotype: Female, micropinned. Dried from ETOH. Label data:- [Holo / type] [Simulium/
(Inseliellum) / littopyga] [FP: TAHITI ITI: 3.5 km E. / Tautira. 0 m, North Road / beach rubble, 18 Jul 2006 / N.
Evenhuis, P. O’Grady] [BPBM 17,838], (ca. S17.7667º W149.1411º).
Paratypes: Five females, micropinned. Five females in ETOH. Labels as for Holotype, but with [Para / type].
Other material: Two adults as slide mounts. Locality data as for types. Three adults each in ETOH,
respectively, from [FP: TAHITI NUI: / North Road, PK 42.7 / 17 Jul 2006, 0 m, beach / rocks. N. Evenhuis], (ca.
S17.6474º W149.3103º); [FP: TAHITI NUI / Trou de Souffler, 0 m / 17 Jul 2006, beach rocks / N. Evenhuis], (aka
Arahoho Blowhole. ca. S17.5256º W149.3909º) and [FP: TAHITI ITI: 3.5 km E./ Tautira, 0 m, North Road/ beach
rubble, 18 Jul 2008/ N. Evenhuis, P. O'Grady].
Etymology. In reference to inhabiting beaches; deriving from litto [= “beach”] + pyga [= “rump”]; hence a
“beach bum” of sorts. The name is treated as a noun in apposition.
Distribution. Known only from Tahiti.
Remarks. In the key to Tahitian simuliid adults then known (Craig 1987: 378), Simulium littopyga would key
out at the first couplet as S. cheesmanae; on the basis of yellow antennae and legs. However, it differs in being
smaller than the smallest known cheesmanae adult, the body is darker and the hypogynial valves (Fig. 12) and
spermatheca (Fig. 13) are markedly different (Craig 1987: cf. his Fig. 4).
Of significance is the restricted beach-inhabiting behaviour of S. littopyga. With exception of S. cheesmanae,
females of which are known to bite humans, all other known females of Tahitian simuliids have flying behaviour
limited to near running fresh water. For S. littopyga, smaller mouthparts, teeth only on one side of the mandibles,
moderately expressed laciniae and, in particular, well-toothed claws suggest ornithophily (e.g. Adler et al. 2004,
Malmqvist et al. 2004).
Simulium (Inseliellum) littosocius Craig & Evenhuis, n. sp.
Figs. 16–29.
Description. Adult female (based on 12 specimens). Body (Figs. 16): overall dark brown, abdomen lighter
ventrally; total length 2.0–2.5 mm. Head (Fig. 17): width 0.66 mm; depth 0.46 mm; postocciput black with sparse
vestiture of short black hairs; frons markedly narrowed ventrally, frons/head width ratio 1.0:14.0; frontal angle 30º.
Eye: interocular distance ca. 0.14 mm; eyes dark red, ommatidia diameter 0.01 mm; ca. 26 rows across and 36
down at mid-eye. Clypeus: width 0.14 mm; mottled dark brown, vestiture of scattered hairs ventrally. Antenna
(Figs. 18): total length 0. 55 mm; evenly dark brown with scape and pedicel paler yellow and subspherical,
flagellomere I angulate and as wide as long; flagellomere II markedly wider than long, II–VIII increasing in length,
flagellomere IX slightly cone-shaped. Mouthparts: feebly developed, ca. 0.25× length of head depth; maxillary
palp (Fig. 19) length 0.55 mm, palpomere V subequal in length to remainder of palp, palpomeres I and II small,
palpomere III small, spherical and darker than other palpomeres, proportional lengths of palpomere III–V 1.0: 1.0:
2.3 respectively; sensory organ spherical, 0.5 length of palpomere III; mandible (Figs. 19, 20) not flared apically,
ca. 17 inner teeth, outer teeth absent; lacinia small, with 9 inner teeth and 10 or 11 outer teeth; cibarium (Fig. 21)
with narrow cornuae sclerotized apically and lightly sculpted, median gap broadly V-shaped. Thorax: length 0.7–
1.0 mm; width 0.7–0.9 mm; scutum black, postpronotal lobe slightly paler than scutum, vestiture slightly longer;
scutellum slightly paler than scutum, vestiture of sparse very fine yellowish hairs; postnotum concolourous with
scutellum; antepronotal lobe with patch of yellow hairs; proepisternum with sparse hairs; anepisternal membrane
bare; katepisternum dark brown, sulcus deep and distinct. Wing (Fig. 22): membrane slightly dusky on anal lobe,
length 2.1–2.3 mm; width 0.8–0.9 mm; anterior veins well expressed; costa and radius with mixture of hairs and
spines; a/b ratio 1.0:4.3; basal cell distinct; CuA not markedly sinuous; A extended nearly to wing margin; narrow
2 2
sclerotised crescent in anal lobe angle. Haltere: tan or white. Legs (Fig. 23): overall dark brown, except hind
basitarsus yellowish with distal dark brown region, row of ventral stout spines poorly expressed; calcipala slightly
more than 0.5 width of basitarsus, slightly flared laterally; pedisulcus well expressed; tarsomere
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FIGURES 16–21. Simulium (I.) littosocius n. sp. (16). Holotype, female Simulium (I) littosocius. In ETOH. Scale bar = 1.0
mm. (17). Frontal view of head. Scale bar = 0.2 mm. (18). Antenna. Scale bar = 0.1 mm. (19). Maxillary palp, lacinia,
mandible. Scale bar = 0.1 mm. (20). Mandible apex. Scale bar = 0.02 mm. (21). Cibarium. Scale bar = 0.1 mm.
SOCIETY ISLANDS BEACH SIMULIIDAE Zootaxa 4311 (3) © 2017 Magnolia Press · 379
FIGURES 22–26. Simulium (I.) littosocius n. sp. (22). Wing. Scale bar = 0.5 mm. (23). Hind basitarsus, calcipala, pedisulcus.
Scale bar = 0.05 mm. (24). Claw & basal tooth. Scale = 0.02 mm. (25). Abdominal tergites (holotype). Scale bar = 0.5 mm.
(26). Hypogynial valves. Scale bar = 0.1 mm.
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FIGURES 27–30. Simulium (I.) littosocius n. sp. FIGURE 30. Simulium (I) littosodalis n. sp. (27). Genital fork. Scale bar =
0.05 mm. (28). Spermatheca. Scale bar = 0.05 mm. (29). Cercus & anal lobe. Scale bar = 0.05 mm. (30). Holotype. In ETOH.
Scale bar = 0.5 mm.
II ca. 2.5 times as long as distal width; claw (Fig. 24) with main talon finely curved and tapered, apex moderately
blunt, basal tooth large, ca. 0.5x length of claw, heel substantial and rounded. Abdomen (Fig. 25): dorsally black,
mottled ventrally, tergites paler and mottled; basal scale dark brown, mottled medially, vestiture of short hairs;
tergite II broadly U-shaped, 3x wider that deep, tergites III–VII lozenge-shaped, 3x time wider than long,
increasing in width posteriorly, vestiture essentially absent from anterior segments, slightly more dense on
posterior segments. Genitalia: sternite VIII evenly pigmented, not depressed medially; hypogynial valves (Fig. 26)
with median gap deeply U-shaped, medial edges strengthened, vestiture of sparse hairs laterally, valves cone-
shaped, rounded apically; genital fork (Fig. 27) with stem smooth, narrowed, not expanded apically, lateral arms
short, lateral plates small, elongated laterally, apodeme moderately expressed; spermatheca ovoid (Fig. 28), small,
dark brown, with slightly wrinkled surface, lacking internal spines, membranous area at junction with spermathecal
duct with fluted edge; cercus in lateral view shallowly cone-shaped, concentration of hairs apically, anal lobe small,
rounded, protruded ventrally (Fig. 29).
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Material. Holotype: Female, micropinned. Dried from ETOH. Label data:- [Holo/ type] [Simulium/
(Inseliellum)/ littosocius] [FP: TAHITI ITI: 3.5 km E. / Tautira, 0 m, North Road / beach rubble, 18 Jul 2006 / N.
Evenhuis, P. O’Grady] [BPBM 17,839], (ca. S17.7667º W149.1411º).
Paratype: Three females micropinned, as for holotype. One microscope slide. Labels with [PARATYPE].
Other material: One microscope slide, two female in ETOH, labels [FP: TAHITI ITI: 0 m, / North Road. PK5
Punatea / Village 19 Jul. [2006] coral / beach rubble. N. Evenhuis], (ca. S17.7370º W149.27185º). Two females,
ETOH, labels [FP: TAHITI NUI: / North Road, PK 20 / 22 Jul 2006, beach / rocks. Evenhuis] (ca. S17.5160º
W149.4054º). One female, ETOH [FP: TAHITI NUI, 0 m, / North Road, PK 48, beach / rocks at Vaihi Riv,
30.III.07 / N. Evenhuis], (ca. S17.6765°, W149.3064°). Two females in ETOH. Label [FP: RAIATEA, 0 m / Baie
Pufau, 21 Mar 2007 / 16.760158°S 151.48886°W / beach rubble, N. Evenhuis].
Etymology. In reference to the association with beaches; deriving from litto [= "beach"] + socius [=
“companion”]; hence a second “beach bum” of sorts. The name is treated as a noun in apposition.
Distribution. Known from Tahiti and Raiatea.
Remarks. Female Simulium littosocius are easily distinguished from those of S. littopyga on the basis of
brown antenna with yellowish scape and pedicel, and browner legs. Additionally, S. littosocius is smaller in size
and the width of the frons in relation to head width is markedly narrowed (Fig. 17) in comparison to that of S.
littopyga (Fig. 2) and S. littosodalis (Fig. 31), below.
Abdominal tergites (Fig. 25) of S. littosocius are well developed, but not as broad as those of S. littopyga (Fig.
11). Simulium littosocius mandibles are parallel-sided, not slightly flared as in S. littopyga (cf. Figs. 4, 20).
Expression of the hypogynial valves differs between the two species (cf. Figs. 12, 26). Differences in the claw tooth
and heel is marked, with both structures much smaller in S. littopyga (cf. Figs. 10, 24).
The presence of S. littosocius on Raiatea, 250 km to the WNW of Tahiti, is not surprising, since the island
shares S. malardei Craig, S. lotii Craig and S. oviceps with Tahiti. Precinctive to Raiatea are S. pufauense Craig, S.
castaneum Craig, S. proctorae Craig and S. bogusium Craig (e.g., Craig & Joy 2000).
Simulium (Inseliellum) littosodalis Craig & Evenhuis, n. sp.
Figs. 30–41.
Description. Adult female (based on 7 specimens). Body (Figs. 30): overall dark blackish brown, abdomen slightly
lighter ventrally; total length 1.5–1.9 mm. Head (Fig. 31): width 0.55–0.58 mm; depth 0.36–0.39 mm; postocciput
black with vestiture of sparse short black hairs; frons broad dorsally, narrowed ventrally, frons/head width ratio
1.0:7.5; frontal angle 50°. Eye: minimum interocular distance ca. 0.08 mm; eyes dark red, ommatidia diameter
0.012 mm; ca 36 down and up at mid-eye. Clypeus: width 0.14 mm; mottled medium brown, vestiture of scattered
hairs. Antenna (Figs. 32): total length 0.40–0.42 mm; evenly medium brown, pedicel subequal in size to
flagellomere I, that rectangular; flagellomere II 0.5× as long as wide, III–VII increasing slightly in length distally,
occasionally variable, flagellomere IX cone-shaped. Mouthparts: feebly developed, ca. 0.27× length of head depth;
maxillary palp (Fig. 33) length 0.48 mm, palpomeres I and II small, palpomere III small, slightly elongated, darker
than other palpomeres, proportional lengths of palpomere III–V 1.0:1.0:2.0, respectively; sensory organ spherical,
0.25x length of palpomere III, opening 0.3× vesicle width; mandibles (Fig. 33) small, not flared distally, straight
sided, ca. 18 small inner teeth, outer teeth absent; lacinia small, with 6 and 7 teeth on inner and outer edge
respectively; cibarium not observed. Thorax: length 1.0–1.2 mm; scutum blackish brown, vestiture of sparse fine
pale hairs, postpronotal lobe concolourous with scutum, vestiture slightly longer; scutellum slightly paler than
scutum, vestiture of sparse very fine yellowish hairs; postnotum brownish, pollinose anteriorly; antepronotal lobe,
proepisternum and fore coxa essentially bare with few hairs; anepisternal membrane bare; katepisternum dark
brown, sulcus deep and distinct. Wing (Figs. 35): membrane slightly smoky on anal lobe, length 1.6–1.8 mm; width
0.8–0.9 mm; anterior veins well expressed, not markedly pigmented; costa with mixture of hairs and spines; Rs
with spines and hairs; a/b ratio 1:5; r-m cross vein slightly pigmentation and extended onto surrounding membrane;
basal medial cell well expressed; CuA not markedly sinuous; A extended nearly to wing margin; crescent shaped
2 2
pigmentation in anal angle. Haltere: tan. Legs (Fig. 34): overall dark brown and hirsute, forelegs with markedly
darker tarsomeres, less so on mid and hind legs; hind tibia slightly curved, with row of ventral stout spines poorly
expressed and absent from distal portion; calcipala half width of hind basitarsus, as long as wide; pedisulcus well
382 · Zootaxa 4311 (3) © 2017 Magnolia Press CRAIG & EVENHUIS